networks//network protocols//HTTPS

HTTPS is HTTP carried over TLS (still loosely called SSL, the name of its retired predecessor, as in *SSL certificate*), normally over TCP/IP: the request-response protocol of the web, encrypted. It is the transport of REST APIs and of most IT integration (REST).

HTTPS is HTTP carried over TLS (still loosely called SSL, the name of its retired predecessor, as in SSL certificate), normally over TCP/IP: the request-response protocol of the web, encrypted. It is the transport of REST APIs and of most IT integration (REST).

The certificate is what lets a browser trust the server: a certificate authority vouches that the key belongs to the domain, so every host serving a domain needs a valid certificate for that name, and a migration has to issue new ones.

It stacks like everything else: HTTPS over TCP/IP over Ethernet over fiber in an office, or over 4G at a remote site (protocol stack).

In a plant it is welcome above the control layer, between applications and toward the cloud, and the wrong tool below it: request-response with no cyclic update, no data quality, no timestamps and an HTTP 500 that cannot say the transmitter lost power 3.8 seconds ago (fault semantics).